Non-volatile semiconductor memory device

Abstract

The non-volatile semiconductor memory device has a circuit which maintains and holds the potentials of bit lines, and either ones of even-bit lines or odd-bit lines are connected to the circuit. When the bit line potential holding circuit is connected to even-bit lines and a block copy is performed, data is first outputted to the even-bit lines, and after the potential of the even-bit line is determined, the bit line potential holding circuit operates. Then, biasing of the potential of the even-bit lines is carried out by the bit line potential holding circuit, the potentials of the bit lines are maintained and held. At the same time, data is outputted to the odd-bit lines and the potentials of the odd-bit lines are determined. Then, a program voltage is supplied to a selected word line, and data is simultaneously written (programmed) in the memory cells connected to the even-bit lines, and the memory cells connected to the odd-bit lines.

1. A non-volatile semiconductor memory device comprising
 a first bit line connected to a first memory cell; 
 a second bit line connected to a second memory cell, the second bit line being adjacent to said first bit line; 
 a bit line shielding circuit, for providing a predetermined shield potential to said second bit line when said first memory cell connected to said first bit line is sensed and for providing said predetermined shield potential to said first bit line when said second memory cell connected to said second bit line is sensed; 
 a data cache circuit for sequentially providing a first data to said first bit line and a second data to said second bit line; 
 a bit line potential holding circuit for holding said first data provided to said first bit line at the time of programming said first memory cell and said second memory cell; and 
 a program circuit for simultaneously programming said first memory cell and said second memory cell while said bit line potential holding circuit holds said first data provided to said first bit line and while the data cache is providing the second data to said second bit line. 
 
   
   
     2. The non-volatile semiconductor memory according to  claim 1  wherein said bit line potential holding circuit has a latch circuit connected to said first bit line. 
   
   
     3. The non-volatile semiconductor memory according to  claim 2  further comprising a first connection transistor connected between said latch circuit of said bit line potential holding circuit and said first bit line. 
   
   
     4. The non-volatile semiconductor memory according to  claim 3  further comprising a second connection transistor connected between said latch circuit of said bit line potential holding circuit and said second bit line. 
   
   
     5. The non-volatile semiconductor memory device according to  claim 1  wherein said first data provided by said data cache circuit is at one of three levels of a high level, a low level or an intermediate level which is between the high level and the low level, and said bit line potential holding circuit holds said first bit line at any one of said three levels. 
   
   
     6. A non-volatile semiconductor memory device comprising:
 a first circuit for sequentially loading data to a first bit line and a second bit line adjacent to said first bit line, said first circuit being connected to one ends of said first bit line and said second bit line; 
 a second circuit for holding a potential of said first bit line, said second circuit being connected to the other end of said first bit line at the time of pro gramming memory cells connected to the first bit line and the second bit line; and 
 a program circuit for programming in memory cells connected to the first bit line and the second bit line simultaneously after said second circuit holds the potential of said first bit line and a potential of said second bit line is maintained. 
 
   
   
     7. The non-volatile semiconductor memory device according to  claim 6  wherein said second circuit holds the first bit line with an intermediate voltage higher than VSS and lower than VDD. 
   
   
     8. The non-volatile semiconductor memory device according to  claim 7  wherein said intermediate voltage is held by said second circuit when programming with smaller threshold voltage shifting is performed to memory cells connected to said first bit line. 
   
   
     9. A non-volatile semiconductor memory device comprising:
 a first memory block consisting of a plurality of first memory cells arranged in matrix, first even bit lines, and first odd bit lines adjacent to the first even bit lines; 
 a second memory block consisting of a plurality of second memory cells arranged in matrix, second even bit lines, and second odd bit lines adjacent to the second even bit lines; 
 a first data cache arranged between said first memory block and said second memory block for loading data to said first and second even bit lines and first and second odd bit lines; and 
 a first bit line potential holding circuit for holding first data at one of said first even bit lines or said first odd bit lines. 
 
   
   
     10. The non-volatile semiconductor memory device according to  claim 9  further comprising a second bit line potential holding circuit for holding second data at one of said second even bit lines or said second odd bit lines. 
   
   
     11. The non-volatile semiconductor memory device according to  claim 9  wherein said first bit line potential holding circuit is arranged at an opposite end of said first memory block to said first data cache. 
   
   
     12. The non-volatile semiconductor memory device according to  claim 10  wherein said first bit line potential holding circuit is arranged at an opposite end of said first memory block to said first data cache; and said second bit line potential holding circuit is arranged at an opposite end of said second memory block to said first data cache. 
   
   
     13. The non-volatile semiconductor memory device according to  claim 9  wherein said first bit line potential holding circuit is located between said first memory block and said second memory block and further holds said second data at one of said second even bit line or said second odd bit line. 
   
   
     14. The non-volatile semiconductor memory device according to  claim 13  further comprising:
 a circuit for biasing located between said first memory block and said second memory block and for biasing said first even or odd bit lines and said second even or odd bit lines. 
 
   
   
     15. The non-volatile semiconductor memory device according to  claim 9  further comprising:
 a third memory block consisting of a plurality of third memory cells arranged in matrix, third even bit lines, and third odd bit lines adjacent to the third even bit lines; 
 a fourth memory block consisting of a plurality of fourth memory cells arranged in matrix, fourth even bit lines, and fourth odd bit lines adjacent to the fourth even bit lines; 
 a second data cache arranged between said third memory block and said fourth memory block for loading data to said third and fourth even bit lines and third and fourth odd bit lines; 
 a second bit line potential holding circuit for holding second data at one of said second even bit lines or said second odd bit lines, and for holding third data at one of said third even bit lines or said third odd bit lines; and 
 a third bit line potential holding circuit for holding fourth data at one of said fourth even bit lines or said fourth odd bit lines. 
 
   
   
     16. The non-volatile semiconductor memory device according to  claim 15  wherein said first bit line potential holding circuit is arranged at an opposite end of said first memory block to said first data cache; said second bit line potential holding circuit is arranged between said second and third memory blocks; said third bit line potential holding circuit is arranged at an opposite end of said fourth memory block to said second data cache. 
   
   
     17. The non-volatile semiconductor memory device according to  claim 11  further comprising a first bias circuit arranged in adjacent to said first bit line potential holding circuit for biasing said first even bit lines or said first odd bit lines. 
   
   
     18. The non-volatile semiconductor memory device according to  claim 16  further comprising:
 a first bias circuit arranged in adjacent to said first bit line potential holding circuit for biasing said first even bit lines or said first odd bit lines; 
 a second bias circuit arranged in adjacent to said second bit line potential holding circuit for biasing said second and third even bit lines or said second and third odd bit lines; and 
 a third bias circuit arranged in adjacent to said third bit line potential holding circuit for biasing said fourth even bit lines or said fourth odd bit lines.